Operating Mechanism Maintenance
1HSB515409-100 en rev2 19
4.9.1 Closing dashpot
Check the oil level in the dashpot by recording the damping effect during operation.
• Connect the circuit-breaker analyser’s sensor to the cam shaft in the operating
mechanism and record a damping curve. Check the damping distance and the
damping time as set out in Figure 4-11. If the measured values for “a” and “b”
are outside the specified values, replace the complete dashpot.
Figure 4-11. Damping curve, Closing dashpot.
4.9.2 Opening dashpot
Check the oil level in the dashpot by recording the damping effect during operation.
• Connect the circuit-breaker analyser’s sensor to the breaker’s shaft and record a
damping curve. Check the damping distance and the damping time as set out in
Figure 4-12. If the recorded curve differs from the correct curve, replace the
complete dashpot.
Figure 4-12. Damping curves, Opening dashpot.
“b”
“a”
“a” = damping distance 15-25 mm
“b” = damping time 80-300 ms
B20015
Wrong
Right Wrong
B20016
To Next Page
Loading...
